Refine rewarded ad handling and session management

Enhanced connection and ad extension logic to handle both acceptance and rejection of ads in AdTest.cs.

Tests/VpnHood.Test/Tests/AdTest.cs

@@ -5,6 +5,7 @@
 using VpnHood.Common.Exceptions;
 using VpnHood.Common.Messaging;
 using VpnHood.Common.Tokens;
+using VpnHood.Common.Utils;
 using VpnHood.Test.Device;
 using VpnHood.Test.Providers;
 
@@ -122,13 +123,17 @@ public async Task RewardedAd_expiration_must_be_increased_by_plan_id(bool accept
 
         // create access token
         var token = accessManager.CreateToken();
-
-        // connect
         var clientProfile = app.ClientProfileService.ImportAccessKey(token.ToAccessKey());
-        await app.Connect(clientProfile.ClientProfileId, ConnectPlanId.PremiumByRewardedAd);
 
-        // assert
-        Assert.AreEqual(acceptAd, app.State.SessionStatus?.AccessUsage?.ExpirationTime==null);
+        // connect
+        if (acceptAd) {
+            await app.Connect(clientProfile.ClientProfileId, ConnectPlanId.PremiumByRewardedAd);
+            Assert.IsNull(app.State.SessionStatus?.AccessUsage?.ExpirationTime);
+        }
+        else {
+            var ex = await Assert.ThrowsExceptionAsync<SessionException>(()=>app.Connect(clientProfile.ClientProfileId, ConnectPlanId.PremiumByRewardedAd));
+            Assert.AreEqual(SessionErrorCode.RewardedAdRejected, ex.SessionResponse.ErrorCode);
+        }
     }
 
     [TestMethod]
@@ -161,8 +166,16 @@ public async Task RewardedAd_expiration_must_be_increased_by_user(bool acceptAd)
         Assert.IsNotNull(app.State.SessionStatus?.AccessUsage?.ExpirationTime);
 
         // show ad
-        await app.ExtendByRewardedAd(CancellationToken.None);
-        Assert.AreEqual(acceptAd, app.State.SessionStatus?.AccessUsage?.ExpirationTime == null);
+        if (acceptAd) {
+            await app.ExtendByRewardedAd(CancellationToken.None);
+            Assert.IsNull(app.State.SessionStatus?.AccessUsage?.ExpirationTime);
+        }
+        else {
+            var ex = await Assert.ThrowsExceptionAsync<SessionException>(() => app.ExtendByRewardedAd(CancellationToken.None));
+            Assert.AreEqual(SessionErrorCode.RewardedAdRejected, ex.SessionResponse.ErrorCode);
+            await Task.Delay(500);
+            await TestHelper.WaitForAppState(app, AppConnectionState.Connected);
+        }
     }
 
     [TestMethod]

VpnHood.Client.App/Services/AppCompositeAdService.cs

@@ -72,12 +72,13 @@ public async Task LoadAd(IUiContext uiContext, string? countryCode, bool forceRe
                 _loadedAdProviderItem = adProviderItem;
                 return;
             }
-            catch (Exception ex) when (ex is UiContextNotAvailableException || ActiveUiContext.Context != uiContext) {
+            catch (UiContextNotAvailableException){
                 throw new ShowAdNoUiException();
             }
 
             // do not catch if parent cancel the operation
             catch (Exception ex) {
+                await VerifyActiveUi();
                 VhLogger.Instance.LogWarning(ex, "Could not load any ad. ProviderName: {ProviderName}.", adProviderItem.Name);
             }
         }
@@ -119,6 +120,9 @@ public async Task<string> ShowLoadedAd(IUiContext uiContext, string? customData,
 
             return _loadedAdProviderItem.Name;
         }
+        catch (UiContextNotAvailableException){
+            throw new ShowAdNoUiException();
+        }
         catch (ShowAdNoUiException) {
             throw;
         }

VpnHood.Client.App/VpnHoodApp.cs

@@ -934,7 +934,7 @@ public Task ExtendByRewardedAd(CancellationToken cancellationToken)
         if (State.SessionStatus?.AccessUsage?.CanExtendByRewardedAd != true)
             throw new InvalidOperationException("Can not extend session by a rewarded ad at this time.");
 
-        return _client.ShowAd(true, cancellationToken);
+        return _client.ShowRewardedAd(cancellationToken);
     }
 
     internal Task RefreshAccount(string[] accountAccessKeys, bool updateCurrentClientProfile)

VpnHood.Client/VpnHoodClient.cs

@@ -797,8 +797,10 @@ private async Task ConnectInternal(CancellationToken cancellationToken, bool all
 
             // show ad
             string? adNetworkName = null;
-            if (sessionResponse.AdRequirement is not AdRequirement.None)
-                adNetworkName = await ShowAd(sessionResponse.AdRequirement is AdRequirement.Rewarded, cancellationToken).VhConfigureAwait();
+            if (sessionResponse.AdRequirement is AdRequirement.Flexible)
+                adNetworkName = await ShowNormalAd(cancellationToken).VhConfigureAwait();
+            if (sessionResponse.AdRequirement is AdRequirement.Rewarded)
+                adNetworkName = await ShowRewardedAd(cancellationToken).VhConfigureAwait();
 
             // usage trackers
             if (_allowAnonymousTracker) {
@@ -911,7 +913,8 @@ internal async Task<ConnectorRequestResult<T>> SendRequest<T>(ClientRequest requ
 
             // close session if server has ended the session
             if (ex.SessionResponse.ErrorCode != SessionErrorCode.GeneralError &&
-                ex.SessionResponse.ErrorCode != SessionErrorCode.RedirectHost)
+                ex.SessionResponse.ErrorCode != SessionErrorCode.RedirectHost &&
+                ex.SessionResponse.ErrorCode != SessionErrorCode.RewardedAdRejected)
                 _ = DisposeAsync(ex);
 
             throw;
@@ -980,8 +983,7 @@ private async Task SendByeRequest(CancellationToken cancellationToken)
         }
     }
 
-    /// <returns>NetworkName</returns>
-    public async Task<string?> ShowAd(bool rewarded, CancellationToken cancellationToken)
+    public async Task<string?> ShowRewardedAd(CancellationToken cancellationToken)
     {
         try {
             if (_adService == null)
@@ -992,21 +994,47 @@ private async Task SendByeRequest(CancellationToken cancellationToken)
 
             _isWaitingForAd = true;
             _clientHost.PassthruInProcessPackets = true;
-            var adResult = rewarded
-                ? await _adService.ShowRewarded(ActiveUiContext.RequiredContext, SessionId.ToString(), cancellationToken).VhConfigureAwait()
-                : await _adService.ShowInterstitial(ActiveUiContext.RequiredContext, SessionId.ToString(), cancellationToken).VhConfigureAwait();
+            var adResult = await _adService
+                .ShowRewarded(ActiveUiContext.RequiredContext, SessionId.ToString(), cancellationToken)
+                .VhConfigureAwait();
 
-            if (!string.IsNullOrEmpty(adResult.AdData) && rewarded)
+            if (!string.IsNullOrEmpty(adResult.AdData))
                 await SendRewardedAd(adResult.AdData, cancellationToken);
 
             return adResult.NetworkName;
         }
         catch (UiContextNotAvailableException) {
             throw new ShowAdNoUiException();
         }
+        finally {
+            _isWaitingForAd = false;
+            _clientHost.PassthruInProcessPackets = false;
+        }
+    }
+
+
+    /// <returns>NetworkName</returns>
+    public async Task<string?> ShowNormalAd(CancellationToken cancellationToken)
+    {
+        try {
+            if (_adService == null)
+                throw new InvalidOperationException("Client's AdService has not been initialized.");
+
+            if (SessionId == 0)
+                throw new InvalidOperationException("Session has not been established.");
+
+            _isWaitingForAd = true;
+            _clientHost.PassthruInProcessPackets = true;
+            var adResult = await _adService
+                .ShowInterstitial(ActiveUiContext.RequiredContext, SessionId.ToString(), cancellationToken)
+                .VhConfigureAwait();
+
+            return adResult.NetworkName;
+        }
+        catch (UiContextNotAvailableException) {
+            throw new ShowAdNoUiException();
+        }
         catch (LoadAdException ex) {
-            if (rewarded)
-                throw new LoadAdException("Could not load any rewarded ad.", ex);
 
             VhLogger.Instance.LogInformation(ex, "Could not load any ad.");
             // ignore exception for flexible ad if load failed
@@ -1045,7 +1073,7 @@ private async Task SendRewardedAd(string adData, CancellationToken cancellationT
         }
         catch (Exception ex) {
             VhLogger.LogError(GeneralEventId.Session, ex, "Could not send the RewardedAd request.");
-            throw new AdException("This server requires a display ad, but AdService has not been initialized.");
+            throw;
         }
     }
 

VpnHood.Server.Access.FileAccessManager/FileAccessManager.cs

@@ -376,10 +376,9 @@ private async Task<SessionResponse> Session_AddUsage(SessionUsage sessionUsage)
             SessionService.CloseSession(sessionId);
 
         // manage adData for simulation
-        if (IsValidAd(sessionUsage.AdData) && SessionService.Sessions.TryGetValue(sessionId, out var session))
-            session.ExpirationTime = null;
+        var isValidAd = string.IsNullOrEmpty(sessionUsage.AdData) ? (bool?)null : IsValidAd(sessionUsage.AdData);
 
-        var res = SessionService.GetSessionResponse(sessionId, accessTokenData, null);
+        var res = SessionService.GetSessionResponse(sessionId, accessTokenData, null, isValidAd: isValidAd);
         var ret = new SessionResponse {
             ErrorCode = res.ErrorCode,
             AccessUsage = res.AccessUsage,

VpnHood.Server.Access.FileAccessManager/Services/SessionService.cs

@@ -157,7 +157,7 @@ private AdRequirement ProcessPlanId(Session session, AccessTokenData accessToken
     }
 
     public SessionResponseEx GetSessionResponse(ulong sessionId, AccessTokenData accessTokenData,
-        IPEndPoint? hostEndPoint)
+        IPEndPoint? hostEndPoint, bool? isValidAd = null)
     {
         // check existence
         if (!Sessions.TryGetValue(sessionId, out var session))
@@ -170,7 +170,7 @@ public SessionResponseEx GetSessionResponse(ulong sessionId, AccessTokenData acc
             session.HostEndPoint = hostEndPoint;
 
         // create response
-        var ret = BuildSessionResponse(session, accessTokenData);
+        var ret = BuildSessionResponse(session, accessTokenData, isValidAd);
         return ret;
     }
 
@@ -182,8 +182,13 @@ public ulong[] ResetUpdatedSessions()
             return sessionIds;
         }
     }
-    private SessionResponseEx BuildSessionResponse(Session session, AccessTokenData accessTokenData)
+    private SessionResponseEx BuildSessionResponse(Session session, AccessTokenData accessTokenData, bool? isValidAd = null)
     {
+        // check if the ad is valid. MUST before access usage
+        if (isValidAd == true)
+            session.ExpirationTime = null;
+
+        // build access usage
         var accessToken = accessTokenData.AccessToken;
         var accessUsage = new AccessUsage {
             ActiveClientCount = 0,
@@ -194,7 +199,16 @@ private SessionResponseEx BuildSessionResponse(Session session, AccessTokenData
             IsPremium = true, // token is always premium in File Access Manager
         };
 
+
+        if (isValidAd == false)
+            return new SessionResponseEx {
+                ErrorCode = SessionErrorCode.RewardedAdRejected,
+                ErrorMessage = "Could not validate the RewardedAd.",
+                AccessUsage = accessUsage
+            };
+
         // validate session status
+        // ReSharper disable once InvertIf
         if (session.ErrorCode == SessionErrorCode.Ok) {
             // check token expiration
             if (accessToken.ExpirationTime != null && accessToken.ExpirationTime < DateTime.UtcNow)
@@ -261,9 +275,9 @@ private SessionResponseEx BuildSessionResponse(Session session, AccessTokenData
             }
 
             // set to session expiration time if session expiration time is shorter than accessUsage.ExpirationTime
-            if (session.ExpirationTime != null && (accessUsage.ExpirationTime == null ||
-                                                   session.ExpirationTime < accessUsage.ExpirationTime))
+            if (session.ExpirationTime != null && (accessUsage.ExpirationTime == null || session.ExpirationTime < accessUsage.ExpirationTime)) {
                 accessUsage.ExpirationTime = session.ExpirationTime.Value;
+            }
 
             accessUsage.ActiveClientCount = otherSessions
                 .GroupBy(x => x.ClientInfo.ClientId)